Combined radio telephone and power-distributing system



De-n 11,1928. 1,695,171

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J. B. HoGE Er AL COMBINED RADIO TELEPHONE AND POWER DISTRIBUTING SYSTEM Filed SeptpB, 1922 4 Sheets-Sheet 2 Dec. 11, 1928. 1,695,171

J. B. HOGE E1' Al.

COMBINED RADIO TELEPHONE AND POWER DISTRIBUTING SYSTEM Filed sept. 1922 '4 sheets-sheet 3 Dern 11, 192s. 1,695,171

J. B. HOGE ET AL COMBINED RADIO TELEPHONE AND POWER DISTRIBUTING SYSTEII Filed sept. a. 1922 4 Sheets-Sheet 4 'Riz Patented Dec. 11, l192s.

UNITED STATES PATENT OFFICE.

JAMES B. HOGE, OF CLEVELAND, OHIO, AND EDWARD E. CLEMENT, OF WASHINGTON, DISTRICT OF COLUMBIA, ASSIGNORS, BY DIRECT AND MESNE ASSIGNMENTS, TO EDWARD F. COLLADAY, OF WASHINGTON, DISTRICT OF COLUMBIA.

COMBINED RADIO TELEPHONE AND POWER-DISTRIBUTING SYSTEM.

Application filed September 8, 1922. Serial No. 586,842.

Our invention relates to radio telephone broadcasting systems, and has for its object the combination of such a system with an electric light, power, or railway system, so that the wires of said system may be employed for controlling, testing, metering, and other purposes.

We attain our object by locating a standard type of radio telephone broadcast receiving instrument at consumers stations on an electric light, power, or railwa system, and broadcasting from a centra station, which may be the central power station or a sub-station belonging to the system. In any case, the radio operators having control of the broadcasting and supervision of reception are provided with switching means whereby they can connect themselves to various radio telephone receiving stations, for purposes of observation and supervision of the system.- At the radio telephone receiving stations, we provide switching connections from the instruments to the current mains, and through these connections effect c-urrent feed to the filament and plate circuits, metering, and under proper conditions bring to the instruments message bearing current generated by electromagnetic waves coming through the ether and intercepted by the outside wire network of the light, power or railway system as an antenna. Since the generation and radiation of these waves is from the central power station, and since the transmitter as well as the substation instruments are grounded, combined ether and wire transmission of the waves will occur, which is highly advantageous for our purpose, according to which the substation instruments are intended for local use only, and are, so far as possible, focussed on the one local transmitting station. This central station is provided with amplifying and modulating apparatus for original matter, and with relaying apparatus for distributing to the subscribers or local consumers programmes and other matters received from a distance. By thus organizing the system so that the subscribers are dependent solely on their local central station for all radio communication, it is possible to unify the service in all respects, and to mal-:e service charges on a fair and accurate basis. For this purpose we prefrably use a .Simple @errent meter, using .e

negligible amount of energy and running at constant speed, with means to register periodlcally in units of time use.

For directive receiving, we may use loop antennae with or without the wire connection, and with or without ground antennae, as circumstances may require. The main purpose of our system is to furnish reliable service under all conditions, over short distances only, and through the use of means tending to cause the subscribers instruments to respond exclusively to their own central station transmitter.

It is to be understood that the principles herein set forth are not limited as to their embodiment to lighting, power or railway circuits as such, but that any conductor or wire circuit capable of carrying and supplying the necessary current and performing the functions described herein, may be used in the present invention. Among such c onductors are telegraph lines, trolley wires, feed wires and cable of lighting, power and railway systems, third rails and underground trolley conductors, and fence and tree wires used by ranchers, lumber interests and others in sparsely settled districts.

Our invention is illustrated in the accompanying drawings, in which:

Fig. l is a typical diagram showing a radio telephone broadcasting system combined with an electric lighting system;

Fig. 2 is a diagram of a single radio telephone receiving station and the connections to the central power station;

Fig. 3 is a similar diagram of a modified arrangement of the system with details of the radio telephone broadcast receiving circuits.

Fig. 4 is a detail ligure of a subscribers instrument equipment.'

Fig. 5 is a simple diagram of an antenna connection for the same.

4Referring to the drawings, Fig. 1 is a condensed diagram showing an electric lighting system with a central power station C, live transformer subst-ations, C C2, C3, Ct, C5, consumers mains M fed from the substations, and feeder mains M, distributing the power from the main generating plant typied by G to the substations. At the centra-l station Sw indicates the usual main switchboard, and Sw a suplemental switchboard for purposes to be described. From this board Sw communication wires 35, 37, 39, 41 extend out to the substations, one pair or more accompanying each feeder cable in the ducts. switchboard is; provided. equippedjvith an automatic selective switch 3G, 3 8, 40 or 42, having a switch arm o1' wipers connected to the incoming line 35, 37, 39 or 41, and contacts over which the wipers are stepped in operation, to connect with local lines to consumers radio telephone receiving stations. Thus at substation C the switch 36 has contacts connected to wires 43, 44, which extend from that substation to the radio telephone receiving stations 43a, 44a. This same substation C carries a feeder main M2 to a second transformer station C5, and the accompanying communication wire 45 extends to a switch 46 at said substation, from which wires 4T, 48 extend to radio telephone receiving stations 47a, 48. This subdivision of the system requires an extra digit in t-he number transmitted from the central operators dial 32 or switchboard Sw at central station C, the switches 34, 3G, and 46 corresponding to first and second selectors and connectors in an automatic telephone system. No detail of the switching circuits or the operating mechanism of the automatic switches is given herein, as such circuits and switches are well known, and of themselves form no part of the present invention, the main feature of which as regards the communication circuits, lies in the ability of the central office operator to automatically connect himself to any part of the system through the minimum number of wires, comprising in this case a single pair from the central station to each substation, and single pairs diverging therefrom to the further subdivisions of the system. The last link in any of these circuits is the individual drop wire, extending from a terminal box to the building in which current is to be used. These drop wires are relatively short, and we contemplate employing them for a double purpose, viz, for communication by phone or otherwise over the wires, and as antennae for the radio telephone receiving instruments, where found expedient or desirable. This will be described hereinafter.

Transformers K are the substation transformers, and transformers K are the house or pole transformers feeding the consumption current mains M10 from the house mains M. The consumption circuits M10 carry translating devices such as lamps L, and also sup ly current to the radio telephone. receivers R, to be presently described. These receive-rs are all standardized and of uniform design and construction, and are calibrated and locked when installed, so as to receive on one common wave lengt-h only, i. e., the wave length allotted to the broadcasting transmitter RT at the central station C. This trans- At each substation...aMsmallmitter may be located at some other point than the central power generating station, and in that case, the switchboard Sw will obviously be located at the same point, and distribution of the communication circuits effected therefrom. Since the local radio telephone receivers RR are al1 uniform and fixed as to their tuning, any tuning required must be on the part of the transmitting operator at switchboard Sw, who is able to listen in and observe the operation of the outlying receiving instruments.

Referring now to Fig. 2, we have therein shown a portion of the power and communication circuits, one radio telephone receiver RR, and the general arrangement of a radio operators switchboard employing plugs and jacks instead of automatic switches for connecting up the communication circuits. In this case the substation operator is called up and by means of plugs and jacks typified at PG, JG, connects the central oiiice C with any desired consumers line. Furthermore we have shown the radio transmitter RT provided with a jack J5 and terminal jacks J2, J3, J4.i provided for lines to substations, whereby any consumers station (telephones being provided) may be connected to the radio transmitter for broadcasting as provided in prior co-pending application of Edward E. Clement, Serial Number 581,829, filed August 14, 1922, Patent No. 1,522,357. This enables the operators to bring in contributions to the broadcasting programme, and also to organize groups of subscribers for broadcast meetings on subjects of common interest, such as chess games, debates. etc. In such cases, the various subscribers lines 30, 31a of any desired group are all plugged in on the same circuit 30-31 to the central broadcasting station, where they may be put on the transmitter RT as a group through jack J5 and suitable amplifying apparatus.

The feeder M2 extends from transformer substation C to the house transformer K which supplies main M carrying lamps L. To this main a socket is connected with which a plug I cooperates to connect the feed wires 17-18 of the radio telephone receiver RR. Current for filament and plate circuits for the loud speaking receiver, and for the meter RM is supplied through this circuit. This meter as shown comprises a motor 22 driving a counter, 24, through a worm gear 23, and taking current through branch wires 19-20. The motor may be of any standard type adapted to the current employed. In the present case alternating current at 60 cycles, single phase, is presupposed, and the motor may be a single phase synchronous or split phase machine, or any other capable of operating at constant speed on a constant potential. The counter is marked in time-use units.

.The receiving instrument RR is equipped W1th antenna 25a, coupler 28, etc., as usual. On the audio side, transformer 14 supplies the armature of the loud speaking receiver 56, its field being fed direct from wires 17-18. For purposes of testing and' observation, the telephone transmitter T may be located in proximity to the horn of the receiver 56. The telephone equipment shown 1s of magneto type, (magneto-generator and ringer being omltted) with induction coil I and receiver t. IVhen placed as shown and plugged through to central station C, the radio opera-tor can listen to the receiver 56 over wires 30-30a-31--31 Referring now to Fig. 3, we have shown therein part of a system similar to that of Fig. 2, but employing an ordinary telephone exchange line 15-16 for a communication circuit. In this case the radio operator at station C has al telephone T t connected to a telephone exchange switchboard Cx from which lines 15-16 extend to subscribers stations A. To listen in to the radio telephone receiver at any consumers station, the radio operator calls the exchange and is plugged through by means of acks JX, J Y or equivalent terminals. In this figure the main generating plant of the system is indicated at C, with feeders M and a house main M supplying lamps L. The circuits M--M typify the usual distribution system. At the consumers station A the details of the radio telephone receiver RR are shown. In this instrument, 1 indicates balancing resistances, 2 the radio frequency transformers, 3 the audio frequency transformers, 4 is a telephone transformer, 5 the armature of a loud speaking receiver, 6 the field of the loud speaker, 7 a tube rectifier, 8 a plate voltage tube rectifier, 9 (as stated) the power transformer, 10 the filament rheostat, 11 a condenser of one microfarad capacity, 12 a leak resistance, 13 a smoothing condenser of ten microfarads capacity, and 14 a step down transformer for the loud speaker. No claim is made herein to this instrument or its circuits, and it is presented as typical only of any instrument suitable for use with the current supplied to the mains M.

The antenna circuit is completed from ground 29 and coil 28 or the equivalent, by wire 25 to plug P2, and so to the lighting means which thus become part of the antenna. Te have shown condensers 26--27 of small capacity in this circuit, but any other known means of preventing current leakage from the lighting mains may be employed. l

For rendering measured service, meter RM is provided, its circuit wires 19-20 being bridged across the main feed wires 17-18 of the radio telephone set. The constant speed motor 22, gears 23 and counter 24 are the same as before. The meter records timeuse, as the circuit 17-18 is closed only when the radio telephone is in service. An advantage in hav.V ng the meter forming a part of the instrument equipment is that the entire equipment is thereby made portable and may be carried to any point where jacks J a or Jb are installed, in the same or another building, and the service will be uniformly metered for all such use. In order to permit such portable use, and for other purposes to be explained, the various parts are assembled in two separate units, as illustrated in Fig. 4, wherein RU is a box containing the power supply, including in the case described, the special transformer 9, w.' th tive windings and the rectifier tubes 7 and 8; and AU is a separate box containing the amplifier tubes, amplifier transformers, and other apparatus. By thus dividing the set, two advantages are gained, viz, the amplifier is removed from immediate proximity to the power supply apparatus, from which it might p'ck up a hum, and second, the power supply box can be made interchangeable with others containinnr different sources of supply, such as a set of storage batteries or a special equipment for adapting 110 volt direct current. supply to the feed circuits of filaments and plates, etc. For this purpose a small motor transformer may be employed, or suitable rheostats and switches. In any case the meter motor is placed in the same box RU with the power equipment and the dial arranged in the side of the box to be read from the outside. IVhere the box contains a storage battery, the meter is thus made a part of the battery unit, and the latter may be detached from the instrument unit AU and taken to a central station or service station for charging. We contemplate organizing this service on such a basis that three classes can be provided for: first those consumers who have alternatfng current supply on their premises, as herein illustrated; second those who have direct current supply only, usually located in a limited business area near the power station, or in a small system; and third those who have no current supply, such as suburban residents and farmers. The third class will use an RU unit with suitable storage batteries for the filamentand plate circuits, meter, etc., and periodically take the unit to a designated service station of the lighting or power company for charging, where the meter will be read and the record of such readings will be periodically used in billing for the service. To save time in such cases, and according to similar practice in other lines of business, the battery units RU may all be made interchangeable, and the meter readings of each unit will be recorded, on receipt and delivery. By this means, a discharged battery can be exchanged at the service station for a freshly charged battery without delay. As the keeping of such records is in accordance with well known principles, detailed description is unnecessary. IVe lay no claim herein to a detachable power unit broadly, but we shall claim herein the interchangeable unit feature, whereby different sources of current supply may be furnished for a standard AU unit or instrument, and shall also claim the mounting of the meter as a part of the power supply unit so that it will always furnish a record of time use. An incidental feature of this arrangement is that the box containing any RU unit may be sealed, so that the battery, transformers, switches, rheostats and meters are secured against interference and the lneter readings thereby made dependable.

A fourth class might be added to the foregoing, including those who have no direct connection to the lighting or power mains, but have local current supply of their Own. This includes suburban and other places equipped with so-called farm lighting outtits. The voltage of such small generating plants is not usually standard, but lower than that on the city distribution systems, hence special RU units must be provided for such service, preferably containing storage batteries to give standard voltages, and a suitable charging set. In any case, regular or special, the meter forms a part of the power supply unit of the radio telephone receiver, and is always connected, as herein described, when the instrument is in use. IYhere standard municipal current supply is available, the inspectors who read the lighting meters will also read the radio telephone receiver meters.

Returning to Fig. 1, the drop wires such as 43, 44, 45, leading from the local distribution centers or substations to the consumers radio telephone receiving stations, may be used as antennae instead of the separate antennae indicated in Fig. 2, or the lighting mains indicated in Fig. 3. In such case plug and jack connections similar to P-Ja of Fig. 3 may be employed, or the antenna connection may be permanent. the drop wire being connected direct to the wire 25 in Fig. 3, with or without the interposition of small capacity condensers, as may be found desirable. The result of making such a connection is shown in a. typical diagram in Fig. 5, wherein RR is the radio telephone receiver, C the central otiice, 30-31 the communication wire, and T the central opcrators telephone. The communication wires 30-31 are here shown connected also to the secondary circuit of the loud speaking transformer on the audio side of the set. so that no telephone is required atthe radio telephone receiving station. The circuit 30-31 is thus at once antenna and an extension of the local radio receiving circuit, over which the operator can test and listen directly.

In operation, a subscriber desirin radio service, plugs his set in on the line M through means of the plug P, Fig. 2, which supplies power to his receiving set RR through conductors 17-18 and to the meter motor 22 through branch wires 19-20. The meter therefore starts into operation and continues to record the length of time the connection is maintained. The receiver RR, being supplied with power will now7 pick up the broadcast signaling to which it is tuned through the antenna circuit 25a-28 and translate it into amplified audible signals through the transformer 14 and loud speaker 56 in a manner as will be understood by those skilled in the art. In the present instance the receiver RR is tuned to the transmitting station RT so that broadcast matter is received therefrom.

Should the subscriber desire connection with the central oiiice C he can do so through the use of his telephone set T, t over the line 30a-31a, through the plug and jack connection J 6 PG at the substation and over line 30-31, all in the usual manner as well understood in the art of telephone communication, details such as switching and signaling means and their use being omitted from the drawing and description for the sake of clearness. Similarly, the central station operator may be connected with the subscribers telephone set over the lines 30-31 and 30a-3la through the substation C'. Thus the subscriber may communicate with the central station for information or to report condition of service. When it is desired to have the subscriber broadcast, the above described connection is established and further extended through jacks J 2 and J5 and suitable cord and plug connections, not shown, to the radio transmitter RT.

For supervision of the quality of reception by the subscribers radio receiver, and controlling the quality of reception, the operator at the central station C makes use of the telephone connection above described to listen in on the audio reproduction from the subscribers loud speaker through the transmitter T, which observation enables the operator to adjust the transmitter to the subscrbers instruments which latter are permanently tuned to a common predetermined wave length.

lVhere storage batteries are used as a source of power supply with the time use meter a part of the power supply unit, as indicated in Fig. 4 the operation is similar to that previously described except that instead of the subscriber connecting with the common distributing system he connects his set with the portable source of power supply, receiving the signaling energy through his inde- T79. TELEPHNY.

pendent aerial as in Figs. 1 and 2, or a distributing system used as an aerial as in Figs. 3 and 5.

We claim:

1. In a system of the class described, a power distributing station and a current supply circuit extending therefrom in a network to a plurality of consumer stations, a broadcasting station associated therewith, a radio telephone receiver at each consumer station having a detector circuit and an energizing circuit, and means for connecting said detector circuit and said energizing circuit to said current supply circuit for simultaneously supplying energizing current and message bearing current therefrom to said radio telephone, together with separate supervision circuits extending from said power distributing station and means at said station to control the same selectively to establish a supervisory relation with the radio telephone receiver at a consumer station.

2. In a system of the class described, a power distributing station and a current supply circuit extending therefrom in a network to a plurality of consumer stations, a broadcastingstation associated therewith, a radio telephone receiver at each consumer station having a detector circuit and an energizing circuit, and means for connecting said detector circuit and said energizing circuit to said current supply circuit for simultaneously supplying energizing current and message bearing current therefrom to said radio telephone, said connecting means including a plurality of paths adapted to pass low frequency current to said energizing circuit and high frequency current only to said detector, together with separate means for selectively establishing a telephonic listening connection between said broadcasting station and a radio telephone receiver at a consumer station.

8. In a combined electric power distribution and radio broadcast system, a central station including a source of power, distributing conductors carrying current therefrom, to points of consumption, by a system of successive subdivision of distributing circuits at substations, a plurality 0f stand ard radio broadcast instruments all tuned to the same wave length located at said points of consumption, means for connectving said instruments to said distributing circuits for current supply, a system of communicating circuits similarly subdivided at the power substations and extending from a central point to said radio broadcast instruments, a radio broadcast transmitter at said central point and means associated therewith for establishing a supervisory circuit by selection over the subdivided communication circuits from the central point to a radio broadcast receiving instrument at a desired point on the system.

4. In a combined electric. power distribution and radio broadcast system, a central station comprising a source of power and substations connected to the central station by feeders, consumers circuits fed from said stations, trunk communication circuits extending between the several substations and the central station, branch communication circuits extending from the substations to consumers stations, radio broadcast receiving instruments connected to the consumers circuits, supervisory means at the central station and means at the several stations to establish supervisory circuits for said receiving instruments extending from said supervisory means by way of the trunk communication circuits and branch circuits to the consumers radio broadcast receiving instruments.

5. A combined power distribution and radio broadcast system comprising a central station including a source of power, a plurality of substations and a plurality of consumers stations with means to conduct power from the central station to the substations and from a substation to its plurality of consumers stations, communication circuits extending through said last mentioned substation from its consumers stations to a central point, radio broadcast receiving instruments at the consumers stations, and means at each station to connect the instrument to the consumers power conductors and to the communication circuit extending to said central point.

In testimony whereof we hereunto affix our signature.

JAMES B. HOGE. EDWARD E. CLEMENT. 

